Tungsten is often deposited in vias, trenches and other holes within a dielectric layer to create plugs other structures within semiconductor devices. The deposition of tungsten is typically by a chemical vapor deposition (CVD) process. As crystalline tungsten fills the hole from all sides, a narrow seam is typically created down the middle of the hole. When using tungsten to fill a hole having a high aspect ratio, such as when filling a via to create a tungsten plug, a portion of the seam often does not close to create a void within the tungsten plug. Therefore, after chemical mechanical polishing (CMP), the exposed areas of the tungsten structures; sometimes referred to below as plug surface areas or plug areas, or tungsten areas or tungsten plug areas, commonly have exposed pits, grooves or other recessed regions created following the CMP procedure. For example, when tungsten is deposited to create a tungsten plug, the tungsten plug may have an internal void but the upper end of the tungsten plug is typically closed. However, after CMP, the upper end of the tungsten plug may be cut back enough to expose the internal void, thus creating the recessed area. The resulting surface topology of such surfaces is thereby degraded which can cause problems, such as poor electrical contact to overlying structures, during later manufacturing steps.